Method of tunneling.



H. A. KUHN & W. W. MACFARREN.

METHOD 0F TUNNELING.

APPL'IOATION FILED 00T. so, 1909.

Nyalaon @MQW UNITED STATES PATENT QFFICE.

HARRY A. KUHN AND WALTER W. .'LVIACFARREN, OF PITTSBURGH, PENNSYLVANIA.

METHOD OF TUNNELING.

Specification of Letters Patent.

Application filed October 3G, 1909.

Patented Api'. 21, 1914. Serial No. 525,531.

To all whom t may concern:

Be it known that we, HARRY A. KUHN and 71WALTER 1V. MACFARREN, citizens of the United States, residing at Pittsburgh, in the county of Allegheny, St-ate of Pennsylvania, have invented a new Method of Tunneling, of which the following is a specification.

Our invention relates to a method of tunneling and more particularly to a method of tunneling in hard rock. Such tunnels are usually constructed by first driving a small pilot tunnel or heading of merely sufiicient sectional area to admit men and tools and for the removal of the material, this heading being subsequently enlarged to the desired size. When the finished cross section of the tunnel is small, the whole tunnel is frequently driven as a heading. The whole sectional area' of the tunnel may be taken out by our improved method, or our method may be used in driving the heading only and the remainder of the rock may be removed in various ways. The application o-f our improved method is, however, full and complete when applied to the heading only. A partly driven head.

ing may be said to consist of two parts, the head and the bore. The head of the heading is the vertical face of the rook which closes one end of the bore. The bore of the heading comprises the roof, floor and side walls or their equiv alents extending from the head to the open end of the heading.

Briefly stated, our invention consists in a method of tunneling comprising the following steps: 1. Forming a number of intersecting slots or channels in the head thus leaving the uncut portions between said slots in the condition of blocks hanging by one end only. 2. Dislodging said hanging blocks by the application of a suitable force or forces. 3. Removing the dislodged material from the heading or tunnel.

lVhere great speed is desirable, as is usually the case in such work our improved method of tunneling would include the following refinements: 1st. Forming one half of the said channels or slots in the head simultaneously. 2nd. Forming the said channels or slots alternately on the second half of the head during which operation the rock would be dislodged and removed from the lirst half of the head By the abo-ve two processes the machinery or laborers used for cutting slots can be kept continually employed and the head can, therefore, be advanced continuously.

Referring to the drawing, Figure 1 is a diagram illustrating in elevation the channels or slots to be formed on one half of the head. Fig. 2 is a diagram illustrating in elevation the channels or slots required to be formed on the full face of a tunnel of the usual rectangular cross section with an arched roof, and Fig. 3 is a plan view showing the condition of the head at the conclusion of the formation of one half of the channels or slots.

In F ig. l the horizontal channels, 1, 2, 3, and a intersect the vertical channels, 5, 6, 7 and S leaving the blocks 9 hanging to the original bed of rock by one end only. As a matter of convenience, especially where ma ehinery is employed for forming the chan-v nels, it is `advisable to proportion the head so that its cross section will be a rectangle composed of two equal squares. The diagram Fig. 1 illustrates the channels to be formed in one of these squares and the rock to be removed therefrom after the channels are formed.

In Fig. 2 the arrangement shown covers the full cross section of a large tunnel in which the blocks 9 cover one half of the head, and blocks 10 the other half of the hea-d and the blocks 11, 12 and 13 material above the head, which is preferably taken down after the head has been advanced some distance as it may then be loaded directly into cars without reaching the ground.

In Fig, 3 at the left side of the head the channels 5, 6, 7 and 8 are shown as just having been completed to their full depth.

The dotted line 14C may represent the bottom of the channels l, 2, 3, and 4. 0n the right side of the head the blocks 9 have been broken ofl at the olearage line 15 and removed. The head as shown in Fig. 3 is now ready for the blocks 9 on the left side, of the heading to be broken off and removed while at the same time the channels l, 2, 3, 4, 5, 6, 7 and 8 are cut in the right side of the head; at the conclusion of which operation the conditions will be the 'saine as shown in Fig. 3 only reversed as regards the two halves of the head.

From the above description, it will be clearly seen that we have provided a simple and efficient method of tunneling in hard rock, which may be either carried out by manual labor with hand tools, or by any suitable rock channeling machinery. 1t will be noted that a tunnel of any cross section and length can be cut by our improved method without the use of explosives, there being no blasting operation. It will also be noted that only a small per centage of the rock is actually disintegrated into fine cuttings and that therefore, t-he power required to effect this disintegration is the minimum, and further that when the cross section of the tunnel is divided as shown by intersecting channels of regular outline and spacing, the material removed is in the form of rectangular blocks of stone, suitable for use in building any sort of large masonry.

It can be shown that with improved machinery this method of tunneling will permit of tunnels being driven at a greater rate of speed than any method now in practical use so far as we are aware.

Vie claiml. A method of tunneling comprising the following steps: 1st, forming simultaneously a number of intersecting slots or channels in one half of the head; 2nd, forming simultaneously similar slots or channels in the other half of the head and at the same time removing the material previously cut, and the material between said previous cuts in the first half of the head and so on alternately @CZ Zz'bz'tum.

2. The method of continuously advancing a tunnel heading comprising the alternate operations of forming slots in the left half of the head to prepare the rock for dislodgment, and at the same time dislodging and removing the rock at the right half of the head, and then forming similar slots at the right half of the head while simultaneously dislodging and removing the rock from the left half of the head.

3. A method of tunneling comprising the formation of intersecting channels or slots of uniform depth in the head said slots being parallel to the bore of the tunnel and at regular intervals, and then breaking out the blocks of stone between said slots, whereby the major part of the excavated material is removed in pieces of regular size and shape suitable for building purposes.

4C. A method of tunneling comprising the following steps: 1st, driving a lower head ing the full width of the tunnel; 2nd, separating the material to be excavated above said heading into blocks hanging by one end only; 3rd, breaking olf said blocks by the application of a suitable force or forces; 4th, removing said blocks from the tunnel.

5. A method of tunneling comprising the following steps: lst, driving a lower heading of the full width of the tunnel; 2nd, separating the material to be excavated above said heading into blocks hanging by one end only; 3rd, breaking olf said blocks by the application of a suitable force or forces; 4th, dropping or lowering said blocks into cars placed under the same; 5th, removing said blocks from the tunnel.

G. A method of rock tunneling comprising the following steps: lst, driving a heading the full width of the tunnel by forming intersecting slots or channels in the head and then dislodging and removing the roel; between said slots; 2nd, beginning at a point some distance in the rear of the head and enlarging the tunnel by forming intersecting slots or channels above the heading and then dislodging and iemoving the rock between the said slots simultaneously with the driving of the heading.

HARRY A. KUHN. TALTER W. MACFARREN.

Vitnesses ESTELLE M. Jol-uvson, CI-ras. LODERMAN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D, C. 

